Beamforming is a technique that allows achieving a particular directional response pattern by means of a plurality of transducers. In a transmission mode, beamforming allows a bundling of radiated power in a particular direction in which a signal is to be sent. That is, beamforming allows a transmitter to have a desired directional radiation pattern. Conversely, in a reception mode, beamforming allows maximum sensitivity in a particular direction from which a desired signal arrives. That is, beamforming allows a receiver to have a desired directional sensitivity pattern. Beamforming can be regarded as a spatial filtering. Beamforming can be done with, for example, acoustic waves and radio waves of any wavelength. Acoustic beamforming may involve an array of loudspeakers or microphones, or both. Radio beamforming may involve an array of antennas.
In general, beamforming involves defining a particular signal relationship between transducers that form part of a beamforming system. A transducer has a particular geometrical position within the beamforming system. The particular signal relationship, which is required to achieve a particular directional response pattern, depends on the respective geometrical positions that the respective transducers have. A suitably programmed processor may calculate the particular signal relationship that is required on the basis of the following input data: the particular direction response pattern that is desired and the respective geometrical positions of the respective transducers. The suitably programmed processor may also take into account respective characteristics of the respective transducers. The particular signal relationship is typically defined by providing a particular transfer function for each individual transducer. In that case, the suitably programmed processor calculates the respective transfer functions for the respective transducers.
US patent application published under number US 2005/0175190 A1 discloses a self-descriptive microphone array that includes a memory, which contains a device description. The device description includes parametric information that defines operational characteristics and configuration of the microphone array. Once connected, the microphone array provides its device description to a computing device. Sound processing software residing within the computing device is then automatically configured for appropriately interacting with one or more audio signals provided by the microphone array. The microphone array may perform a self calibration for automatically updating the device description. The self calibration is performed either upon connection to the computing device, or upon regular or user-specified intervals.